# 15 19 26 triangle

### Obtuse scalene triangle.

Sides: a = 15   b = 19   c = 26

Area: T = 140.7122472795
Perimeter: p = 60
Semiperimeter: s = 30

Angle ∠ A = α = 34.7288341173° = 34°43'42″ = 0.60661238972 rad
Angle ∠ B = β = 46.18769385396° = 46°11'13″ = 0.80661141489 rad
Angle ∠ C = γ = 99.08547202874° = 99°5'5″ = 1.72993546074 rad

Height: ha = 18.76216630393
Height: hb = 14.81218392415
Height: hc = 10.82440363688

Median: ma = 21.5
Median: mb = 18.98802528961
Median: mc = 11.13655287257

Inradius: r = 4.69904157598
Circumradius: R = 13.1655144235

Vertex coordinates: A[26; 0] B[0; 0] C[10.38546153846; 10.82440363688]
Centroid: CG[12.12882051282; 3.60880121229]
Coordinates of the circumscribed circle: U[13; -2.07987069845]
Coordinates of the inscribed circle: I[11; 4.69904157598]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 145.2721658827° = 145°16'18″ = 0.60661238972 rad
∠ B' = β' = 133.813306146° = 133°48'47″ = 0.80661141489 rad
∠ C' = γ' = 80.91552797126° = 80°54'55″ = 1.72993546074 rad

# How did we calculate this triangle?

Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS. ### 1. The triangle circumference is the sum of the lengths of its three sides ### 2. Semiperimeter of the triangle ### 3. The triangle area using Heron's formula ### 4. Calculate the heights of the triangle from its area. ### 5. Calculation of the inner angles of the triangle using a Law of Cosines ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

See more informations about triangles or more information about solving triangles.